This KB article outlines the steps on how to import blog posts from Wordpress for v8 and v10. Please check your version and here.
If you have a WordPress blog you can import existing post content into your new Sitebuilder blog.
1. Click Blog
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Blog icon
2. Click Wordpress Import
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Wordpress import
Exporting your Wordpress blog posts
If you are unsure how to export your existing Wordpress posts there is a quick guide on the importing page.
3. Select the file you would like to import and click Import
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Wordpress file import